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Thermos

40
Size Chart
Colour
Grey Marle
Size

Just like a hot cuppa, the Thermos singlet warms you from the inside out. Worn under your favourite cycle top, Heatwave™ Merino wicks away sweat while WindFoil™ softshell shields your torso from biting breezes without any flap.

▸ Features
  • WindFoil™ front blocks chilly winds.
  • Heatwave™ hi-performance thermal bodywear combines a merino inner layer with a fast-drying polyester outer.
  • Flat seams for enhanced comfort.
  • 'Snug-as-a-bug' fit keeps the fabric against your skin to wick sweat away.
  • WhaleTail™ cut keeps you tucked in.
  • Designed & made by us in Aotearoa | New Zealand.
▸ Tech

▸ 
A bi-component thermal fabric combining 51% merino wool and 49% polyester. Superfine 18.5 micron New Zealand merino wicks sweat away from your skin while the polyester provides a durable, non-pill outer. Lightweight at just 160gm/m2 and machine washable. Developed by Ground Effect and knitted just for us.
  • Composition: 51% merino; 49% polyester
▸ Man vs Wild
Merino is unrivalled for comfort as a body layer. It absorbs more moisture than synthetic fibres, mopping up excess sweat rather than letting it settle and cool on your skin. However high-aerobic activities like cycling will often overload ordinary merino. Heatwave's polyester component repels moisture to avoid total saturation of the fabric - so it dries faster to keep you toasty.
▸ Snug-as-a-Bug Fit
Heatwave™ Merino tops are intended to hug your body, ensuring the fabric sits against your skin to wick sweat away - keeping you dry and not chilling out.
▸ Hot 'n' Cold
As a single garment Heatwave™ Merino regulates your temperature through a wide range of conditions. Delivering comfort in all but the hottest climes. Yet it is versatile enough to layer under a WindFoil™, microFoil™ or HydroFoil™ shell in winter.

▸ 
WindFoil™ combines the insulative benefits of a polyester micro-fleece liner with a smooth, highly water resistant, softshell exterior. A totally windproof, yet highly breathable membrane is sandwiched between the inner and outer fabrics providing effective protection in cold, dry conditions.
  • Composition: 100% polyester with PU membrane.
  • 100% windproof.
  • Durable water-repellent (DWR) finish on face fabric.
  • Breathability: 4000gm per sq.m per 24hr.

▸ Composite Tops
For short trips in stable weather conditions, a Ground Effect composite top lets you travel light and fast with just a single thermal layer. These designs combine a WindFoil™ front with a breathable Thermostat™ fleece or Heatwave™ Merino back. A long front zip for ventilation allows you to manage your body temperature through a wide range of conditions. Apparently you can have your cake and eat it too.

▸ WhaleTail™
Ground Effect tops are cut with extra length in the back... and in the sleeves too. So when you stretch out in search of the perfect downhill position, neither your shirttail or sleeves will ride-up to expose your back or wrists to the elements.

▸ More than Kiwi Made
Ground Effect clothing is crafted right here in New Zealand. Has been ever since we started back in 1994. Manufacturing locally works for us. We operate a quick-response system - holding minimal stock of any one item, but churning out a few more quick-smart when the pile gets low. The upshot is that we are seldom caught with our shelves empty, so orders get despatched the same day you place them.

▸ Weight
130 gm
▸ Video

▸ FAQ

▸ Why is Heatwave Merino so comfortable next-to-skin?
  • Heatwave combines the comfort, warmth and low-odour properties of merino wool with the durability of polyester. Merino wool absorbs more moisture than synthetic fibres like polyester or polypropylene. This makes it very effective in dealing with excess sweat - it is absorbed into the fabric rather than settling (and cooling) on your skin. The polyester component repels moisture which avoids total saturation of the fabric - helping it to dry faster. The strength of the polyester also maintains the shape of the garment and minimises wear 'n' tear and pilling.
  • The Baked Alaska, Popsicle and Hot Toddy are intended to be used as a stand alone cycle top in cool, as opposed to cold, conditions.
  • The Thermos, Ristretto and Submerino are all base layers - best worn directly against your skin.
  • The Median Strip, Berglar and Hoola are riding jerseys, with additional features including three rear pockets and long front zips. For use in both hot and cold climes and versatile enough to wear as an insulation layer in winter.

▸ Heatwave™ Merino vs InfraRed™ polyester?
  • Your base layer is a critical part of your clothing system in cold conditions. Its primary purpose is to move excess sweat away for your body to minimise the cooling effect of any dampness against your skin.
  • Heatwave™ Merino is sensational when you're on-the-go in cold, dry conditions. It keeps you warm by absorbing and dispersing any sweat, letting it evaporate faster. However you can 'overload' the fabric with prolonged use or in wet conditions. At that point it no longer has great thermal properties. So, an excellent choice while you're moving and expending energy, but can cause you to chill out if stopped for an extended time.
  • InfraRed's polyester fibres absorb almost no moisture - so the fabric dries considerably faster when you stop exercising. A moisture management treatment plus a brushed finish against your skin helps disperse sweat (but not quite as effectively as merino does). In addition the FarRed™ mineral print against your skin reduces 'far infrared' heat loss. A good choice in wet conditions and if you anticipate any faffing around on your ride, or on multi-day adventures when you need your clothing to dry overnight.
  • Heatwave™ has the additional benefits of the low-odour properties of merino wool. The FarRed™ mineral print also disguises smell - but to a lesser extent in our experience.

▸ Washing

  • All Ground Effect clothing enjoys a warm 40ºC machine wash. Try to avoid cold-water detergents and those with bleach, 'oxygen whitener' or fabric softener.
    • The cold-water varieties have little enzymes that are super-charged to brave the cold but can damage technical fabrics and cause skin irritation. 
    • Bleach rots natural fibres like merino, strips the dye, attacks laminates of waterproof fabrics and can also cause skin irritation.
    • Sodium Percarbonate (the main ingredient in oxygen whitener) can make colours run.
    • Fabric softener and stuff containing it like wool wash destroys the water repellent finish on waterproof and water resistant fabrics, and can cause colours to run. 
  • As a rule of thumb, a product that is easy on the planet is also easy on your body. Select a mild plant-based soap like EcoverEcostoreEarthwise or Aware.
  • Hand washing is sometimes the only option on tour, but a washing machine rinses more thoroughly and is preferable if you have the choice.
  • Most Ground Effect gear dries super-fast so hanging on the line or drooping over the bedpost is generally the best option. High heat can damage some fabrics so if you do take your threads for a spin, set the device on 'medium' or 'warm' rather than hot. A lap in the dryer is recommended for your rain jacket, after it has dried on the line, as it helps recharge its water repellent finish. 

  • Wash colours separately.

Customer Reviews

4.9 Based on 40 reviews
5 Star
93% 
37
4 Star
7% 
3
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0% 
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2 Star
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We value your feedback. If you're stoked with your Ground Effect kit then you might like to share it (the review not the gear) with your mates. Thanks again.

    PS
    01/07/2019
    Paul S.
    Australia Australia

    Thermos vest review

    Excellent undershirt for cold winter mornings in Melbourne. Worn at zero and 1 degrees at 6am and provided perfect warmth. The Windfoil chest protector is a beauty. Highly recommended.

    DL
    28/06/2019
    David L.
    Australia Australia

    Thermos - toasty

    Wore this for the first time riding with the temp at 6 deg. Kept my front toasty warm and back dry. Temp got up to 20 deg and the front got warm, back the back wicked the moisture away brilliantly.

    LW
    13/06/2019
    Lee W.
    New Zealand

    Thermos

    Excellent for wearing under medium weight tops. When the temp drops below zero I wear a Frosty Boy but find that too warm when the temp is in the +3 range. A thermos under a medium weight long sleeve top is perfect in the 3 to 10 degrees. As suggested in other reviews went a size smaller than usual and fits perfectly under another top.

    DC
    12/06/2019
    Daniel C.
    Australia

    The undergarment is da goods

    I bought one of these last year and it gets used that often in the cooler weather that I bought another one. It's great for use when it's just too cool for just a jersey, but even better when you need to layer up for the really cold days. The combination of wind stopper and merino is a WINNER! You won't regret buying one of these.

    RN
    05/06/2019
    Rachel N.
    New Zealand

    Thermally Thermos

    Had slight reservations that this little number could keep one so warm but no fear it really does.....grab one today!

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